The early light series composite trusses, such as Troutner U.S. Pat. Nos. 3,137,899, (1964) and Troutner 3,268,251 (1966) were designed so that either the top or bottom chord rested on top of the end bearing wall or other horizontal support. Where it was desired to hang the truss from the side of the support wall or horizontal support, special expensive, custom made hangers were fabricated. Because of the weight and cost of such hangers, they were seldom used even though there was a great need for hanger supported trusses.
In 1974, Gilb was granted a patent on an improved composite truss, but it also required the same expensive custom made hanger.
The first integral design for hanging light series composite trusses was presented by Peters in U.S. Pat. No. 3,961,455 (1976). Peters described several solutions, all of which required a welded bracket and a long strengthening bar spanning the distance between two pin joints. The metal strengthening bar either consists of a heavy channel member which envelopes three sides of the upper chord or requires a long center slot in the upper chord.
While a practical method of hanging light series trusses remained unsolved, Gilb found an economical means for hanging medium and heavy load series composite trusses which have double timber members in the top chord, see Gilb, U.S. Pat. No. 4,003,179 (1977). These hangers, however, were unsuitable for light series trusses having single timber members in the chords.
Finally, it is well known that where the trusses must span 12 to about 60 feet, the bearing walls cannot be built to zero tolerance. The Peters patent does not disclose any adjustment in the hanger to compensate for the misalignment of the bearing walls.